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Hi guys,

let's see if someone had the same problem. I clamp the soudnboard on my MDF solera with cam clamps. Some of them just release. No matter how hard I tighten, sooner or later they just release. Not all of them. I really can't understand why this is happening.

Thanks

Yeah I have that problem too with two of my clamps. They can probably be fixed some how.

Protective cork pads on a clamp could be the problem. When you tighten the clamp, the pad compresses, but after a while the compression dissipates laterally. The same thing can happen with a circular screw clamp on a rubber hose. Over tightening the clamp makes it worst. Just snug the clamp enough to do the job.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

This has happened to some of my clamps where the steel bar had worn smooth from repeated use on the same spot and so there wasn't enough friction to stop the cam portion from sliding. I cut a few little notches with a hack saw to leave a rough surface on the bar and they work fine again now.

Happens to me as well. The bars on my clamps are not worn, so, in my case, I think it's what Alex is describing.

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George :-)

I see... so it's relatively common. I am surprised since I did not make much use of them as I am an amateur. I'll see if Incan fix them.

What brand of clamps are they Enrico, or did you make them?

They are klemmsia. The standard cam clamps in every luthier's workshop. The bar has always been smooth and cork is ok. So I guess its just broken.